Ermanno Borra thinks that aliens just may be winking at us from across the void—that they're trying to make contact using a method that even we primitive earthlings might grasp, and that they come (or perhaps will come, eventually) in peace.
The Université Laval astronomer realizes it's a bold claim, and will be rigorously challenged by his peers. But he's adamant that it's not a preposterous one.
"The search for extraterrestrial life is a very legitimate scientific endeavour," he says. "It's not something crazy."
In a peer-reviewed paper published in this month's Publications of the Astronomical Society of the Pacific, Borra and grad student Eric Trottier wrote that an analysis of the spectra—the intensity of the light as a function of many wavelengths—of 2.5 million stars found minuscule but highly peculiar modulations from 234 of them. Like, really tiny: the separations detected were 10-9 to 10-15 seconds apart.
The pair examined the stars catalogued in the Sloan Digital Sky Survey, a 3D map of the universe that over the past 16 years catalogued over three million astronomical objects. They found that the 234 stars were also in the same spectral range as our Sun's (for the record, the F2 to K1 spectra range). With instrumental or calculation error and other possibilities accounted for and eliminated as possible sources of the readings, Borra and Trottier suggest that the signals may possibly have come from extraterrestrial intelligence trying to alert humans to their existence.
He speculates that it would be possible for an alien life form to shine a laser into outer space, superposing its light over that of its host star. The signal could be detected in the spectrum of the star, containing as it does the light of both the star and the laser.
The paper, excitingly titled "Discovery of Peculiar Periodic Spectral Modulations in a Small Fraction of Solar-type Stars," has already generated a lot of media coverage and controversy. It hasn't helped that overzealous and click-hungry headline writers use phrases like "probably from aliens" when discussing the work. An investigation bySnopes.com debunked the "probably" part, making it clear neither scientist was willing to use the word in a formal academic paper—something that likely would have resulted in the pair being pilloried by their colleagues.
Several scientists involved in the search for extraterrestrial intelligence (ETI) have been either cautious or dismissive of their claims. Snopes notes that Breakthrough Listen, a search venture funded by Russian entrepreneur Yuri Milner and backed by Stephen Hawking and Mark Zuckerberg, isn't popping champagne corks yet; neither is theSETI Research Center at UC Berkeley.
But Borra, a professor of physics at Laval who received his PhD from the University of Western Ontario, certainly doesn't come across as a charlatan or a fool. And he knows that he needs a whole lot more evidence to back up his hypothesis. The scientific method is built on testing hypotheses and poking holes in them, so he never makes the claim that the signals are definitively from aliens. He merely carefully suggested that it's possible that they are. He suspects that those who dismiss his paper outright probably didn't read it in detail. The same would apply to those who jump to conclusions that aliens are definitely reaching out to us, based on his curious finding.
"The ETI hypothesis is a strange one, so it's normal to be skeptical," he says. "But it's not something crazy. Again, it's a field of very legitimate scientific research."
One that doesn't come cheap: for instance, the SETI Institute-operated Allen Telescope Array in northern California has burned through $50 million in about a decade, half of which came from Microsoft co-founder Paul Allen. The Breakthrough Listen project's 10-year, $100 million funding is courtesy of Russian tycoon Yuri Milner. Even the Sloan Digital Sky Survey was mostly funded via the philanthropic Alfred P. Sloan Foundation. No government is seriously investing in the search for ETI (although President-elect Trump has said he will make space exploration great again, without offering any details). Still, there seems to be enough curiosity about our new frontiers and new life forms--whether they be in deep space or in the deep ocean—to spur individuals to generously fund scientific research alongside governments.
Borra says that if—and he admits it's a big if—his hypothesis is supported by enough solid evidence that it can be assumed that the source of these infinitesimal changes in the light pulses' intensity is indeed the result of extraterrestrial communication, he says it would be "one of the most important things ever done on Earth."
The method of communication is also flexible enough that the source—a hypothetical alien civilization—could also include vital information about themselves, including pictures.
This isn't the first time Borra has speculated that a specific kind of light pulse might have originated with ETI. A 2012 paper he authored predicted that the signals grad student Trottier found in the reams of data were consistent with what he believed an ETI signal would look like. Basically, light pulses are an easy way to send signals and have them seen by a distant recipient. The paper's abstract reads: "Theory, confirmed by published experiments, shows that periodic signals in spectra can be easily generated by sending light pulses separated by constant time intervals.... [T]echnology now available on Earth could be used to send signals having the required energy to be detected at a target located 1000 lt-yr away. Extraterrestrial Intelligence (ETI) could use these signals to make us aware of their existence."
Borra is the first to admit that more work—a lot more work—is needed before we can be sure that something out there is reaching out to us. But any civilization trying to make contact likely wouldn't be interested in Earth as a target for conquest, enslavement or nourishment. He believes any such species would "certainly have technology far more advanced than we do," and that they would very likely be peaceful.
The theory is, if aliens can get it together enough to be able to create technology that looks to life beyond their solar system, they have advanced enough as a species to put their primitive, warlike impulses behind them. They don't need to slaughter or enslave us. It's a nice thought, but unfortunately, wholly speculative.
He further suspects that spectral modulations may be just one method aliens are using to reach out across the galaxy. There may be others that are beyond our comprehension, using technologies we haven't yet grasped.
The pace at which our technology has advanced in just the last 50 or 60 years gives Borra some perspective on what is feasible in terms of communications. From postage-stamped letters to Skype, the leap has been immense. Borra doesn't know where or how it will ever stop advancing, and that, he says, is encouraging in the long run.
"Intuitively, I suspect that civilizations that are more advanced are peaceful," he says. "So anyone trying to contact us would be very nice people, for obvious reasons."
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